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2022-06-15xfs: fix variable state usageDarrick J. Wong1-2/+1
The variable @args is fed to a tracepoint, and that's the only place it's used. This is fine for the kernel, but for userspace, tracepoints are #define'd out of existence, which results in this warning on gcc 11.2: xfs_attr.c: In function ‘xfs_attr_node_try_addname’: xfs_attr.c:1440:42: warning: unused variable ‘args’ [-Wunused-variable] 1440 | struct xfs_da_args *args = attr->xattri_da_args; | ^~~~ Clean this up. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2022-06-15xfs: fix TOCTOU race involving the new logged xattrs control knobDarrick J. Wong4-15/+9
I found a race involving the larp control knob, aka the debugging knob that lets developers enable logging of extended attribute updates: Thread 1 Thread 2 echo 0 > /sys/fs/xfs/debug/larp setxattr(REPLACE) xfs_has_larp (returns false) xfs_attr_set echo 1 > /sys/fs/xfs/debug/larp xfs_attr_defer_replace xfs_attr_init_replace_state xfs_has_larp (returns true) xfs_attr_init_remove_state <oops, wrong DAS state!> This isn't a particularly severe problem right now because xattr logging is only enabled when CONFIG_XFS_DEBUG=y, and developers *should* know what they're doing. However, the eventual intent is that callers should be able to ask for the assistance of the log in persisting xattr updates. This capability might not be required for /all/ callers, which means that dynamic control must work correctly. Once an xattr update has decided whether or not to use logged xattrs, it needs to stay in that mode until the end of the operation regardless of what subsequent parallel operations might do. Therefore, it is an error to continue sampling xfs_globals.larp once xfs_attr_change has made a decision about larp, and it was not correct for me to have told Allison that ->create_intent functions can sample the global log incompat feature bitfield to decide to elide a log item. Instead, create a new op flag for the xfs_da_args structure, and convert all other callers of xfs_has_larp and xfs_sb_version_haslogxattrs within the attr update state machine to look for the operations flag. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2022-05-30Merge branch 'guilt/xfs-5.19-larp-cleanups' into xfs-5.19-for-nextDave Chinner1-12/+2
This series contains a two key cleanups for the new LARP code. Most of it is refactoring and tweaking the code that creates kernel log messages about enabling and disabling features -- we should be warning about LARP being turned on once per mount, instead of once per insmod cycle; we shouldn't be spamming the logs so aggressively about turning *off* log incompat features. The second part of the series refactors the LARP code responsible for getting (and releasing) permission to use xattr log items. The implementation code doesn't belong in xfs_log.c, and calls to logging functions don't belong in libxfs -- they really should be done by the VFS implementation functions before they start calling into libraries. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-30Merge branch 'guilt/xfs-5.19-recovery-buf-cancel' into xfs-5.19-for-nextDave Chinner1-6/+8
As part of solving the memory leaks and UAF problems in the new LARP code, kmemleak also reported that log recovery will leak the table used to hash buffer cancellations if the recovery fails. Fix this problem by creating alloc/free helpers that initialize and free the hashtable contents correctly. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: move xfs_attr_use_log_assist usage out of libxfsDarrick J. Wong1-11/+1
The LARP patchset added an awkward coupling point between libxfs and what would be libxlog, if the XFS log were actually its own library. Move the code that sets up logged xattr updates out of libxfs and into xfs_xattr.c so that libxfs no longer has to know about xlog_* functions. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: move xfs_attr_use_log_assist out of xfs_log.cDarrick J. Wong1-3/+3
The LARP patchset added an awkward coupling point between libxfs and what would be libxlog, if the XFS log were actually its own library. Move the code that enables logged xattr updates out of "lib"xlog and into xfs_xattr.c so that it no longer has to know about xlog_* functions. While we're at it, give xfs_xattr.c its own header file. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: convert buf_cancel_table allocation to kmalloc_arrayDarrick J. Wong1-1/+1
While we're messing around with how recovery allocates and frees the buffer cancellation table, convert the allocation to use kmalloc_array instead of the old kmem_alloc APIs, and make it handle a null return, even though that's not likely. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: refactor buffer cancellation table allocationDarrick J. Wong1-6/+8
Move the code that allocates and frees the buffer cancellation tables used by log recovery into the file that actually uses the tables. This is a precursor to some cleanups and a memory leak fix. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: don't leak btree cursor when insrec fails after a splitDarrick J. Wong1-3/+5
The recent patch to improve btree cycle checking caused a regression when I rebased the in-memory btree branch atop the 5.19 for-next branch, because in-memory short-pointer btrees do not have AG numbers. This produced the following complaint from kmemleak: unreferenced object 0xffff88803d47dde8 (size 264): comm "xfs_io", pid 4889, jiffies 4294906764 (age 24.072s) hex dump (first 32 bytes): 90 4d 0b 0f 80 88 ff ff 00 a0 bd 05 80 88 ff ff .M.............. e0 44 3a a0 ff ff ff ff 00 df 08 06 80 88 ff ff .D:............. backtrace: [<ffffffffa0388059>] xfbtree_dup_cursor+0x49/0xc0 [xfs] [<ffffffffa029887b>] xfs_btree_dup_cursor+0x3b/0x200 [xfs] [<ffffffffa029af5d>] __xfs_btree_split+0x6ad/0x820 [xfs] [<ffffffffa029b130>] xfs_btree_split+0x60/0x110 [xfs] [<ffffffffa029f6da>] xfs_btree_make_block_unfull+0x19a/0x1f0 [xfs] [<ffffffffa029fada>] xfs_btree_insrec+0x3aa/0x810 [xfs] [<ffffffffa029fff3>] xfs_btree_insert+0xb3/0x240 [xfs] [<ffffffffa02cb729>] xfs_rmap_insert+0x99/0x200 [xfs] [<ffffffffa02cf142>] xfs_rmap_map_shared+0x192/0x5f0 [xfs] [<ffffffffa02cf60b>] xfs_rmap_map_raw+0x6b/0x90 [xfs] [<ffffffffa0384a85>] xrep_rmap_stash+0xd5/0x1d0 [xfs] [<ffffffffa0384dc0>] xrep_rmap_visit_bmbt+0xa0/0xf0 [xfs] [<ffffffffa0384fb6>] xrep_rmap_scan_iext+0x56/0xa0 [xfs] [<ffffffffa03850d8>] xrep_rmap_scan_ifork+0xd8/0x160 [xfs] [<ffffffffa0385195>] xrep_rmap_scan_inode+0x35/0x80 [xfs] [<ffffffffa03852ee>] xrep_rmap_find_rmaps+0x10e/0x270 [xfs] I noticed that xfs_btree_insrec has a bunch of debug code that return out of the function immediately, without freeing the "new" btree cursor that can be returned when _make_block_unfull calls xfs_btree_split. Fix the error return in this function to free the btree cursor. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: assert in xfs_btree_del_cursor should take into account errorDave Chinner1-1/+7
xfs/538 on a 1kB block filesystem failed with this assert: XFS: Assertion failed: cur->bc_btnum != XFS_BTNUM_BMAP || cur->bc_ino.allocated == 0 || xfs_is_shutdown(cur->bc_mp), file: fs/xfs/libxfs/xfs_btree.c, line: 448 The problem was that an allocation failed unexpectedly in xfs_bmbt_alloc_block() after roughly 150,000 minlen allocation error injections, resulting in an EFSCORRUPTED error being returned to xfs_bmapi_write(). The error occurred on extent-to-btree format conversion allocating the new root block: RIP: 0010:xfs_bmbt_alloc_block+0x177/0x210 Call Trace: <TASK> xfs_btree_new_iroot+0xdf/0x520 xfs_btree_make_block_unfull+0x10d/0x1c0 xfs_btree_insrec+0x364/0x790 xfs_btree_insert+0xaa/0x210 xfs_bmap_add_extent_hole_real+0x1fe/0x9a0 xfs_bmapi_allocate+0x34c/0x420 xfs_bmapi_write+0x53c/0x9c0 xfs_alloc_file_space+0xee/0x320 xfs_file_fallocate+0x36b/0x450 vfs_fallocate+0x148/0x340 __x64_sys_fallocate+0x3c/0x70 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa Why the allocation failed at this point is unknown, but is likely that we ran the transaction out of reserved space and filesystem out of space with bmbt blocks because of all the minlen allocations being done causing worst case fragmentation of a large allocation. Regardless of the cause, we've then called xfs_bmapi_finish() which calls xfs_btree_del_cursor(cur, error) to tear down the cursor. So we have a failed operation, error != 0, cur->bc_ino.allocated > 0 and the filesystem is still up. The assert fails to take into account that allocation can fail with an error and the transaction teardown will shut the filesystem down if necessary. i.e. the assert needs to check "|| error != 0" as well, because at this point shutdown is pending because the current transaction is dirty.... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: don't assert fail on perag references on teardownDave Chinner1-2/+1
Not fatal, the assert is there to catch developer attention. I'm seeing this occasionally during recoveryloop testing after a shutdown, and I don't want this to stop an overnight recoveryloop run as it is currently doing. Convert the ASSERT to a XFS_IS_CORRUPT() check so it will dump a corruption report into the log and cause a test failure that way, but it won't stop the machine dead. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-27xfs: avoid unnecessary runtime sibling pointer endian conversionsDave Chinner1-14/+33
Commit dc04db2aa7c9 has caused a small aim7 regression, showing a small increase in CPU usage in __xfs_btree_check_sblock() as a result of the extra checking. This is likely due to the endian conversion of the sibling poitners being unconditional instead of relying on the compiler to endian convert the NULL pointer at compile time and avoiding the runtime conversion for this common case. Rework the checks so that endian conversion of the sibling pointers is only done if they are not null as the original code did. .... and these need to be "inline" because the compiler completely fails to inline them automatically like it should be doing. $ size fs/xfs/libxfs/xfs_btree.o* text data bss dec hex filename 51874 240 0 52114 cb92 fs/xfs/libxfs/xfs_btree.o.orig 51562 240 0 51802 ca5a fs/xfs/libxfs/xfs_btree.o.inline Just when you think the tools have advanced sufficiently we don't have to care about stuff like this anymore, along comes a reminder that *our tools still suck*. Fixes: dc04db2aa7c9 ("xfs: detect self referencing btree sibling pointers") Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-23Merge branch 'guilt/xfs-5.19-misc-3' into xfs-5.19-for-nextDave Chinner1-1/+1
2022-05-23xfs: share xattr name and value buffers when logging xattr updatesDarrick J. Wong2-12/+55
While running xfs/297 and generic/642, I noticed a crash in xfs_attri_item_relog when it tries to copy the attr name to the new xattri log item. I think what happened here was that we called ->iop_commit on the old attri item (which nulls out the pointers) as part of a log force at the same time that a chained attr operation was ongoing. The system was busy enough that at some later point, the defer ops operation decided it was necessary to relog the attri log item, but as we've detached the name buffer from the old attri log item, we can't copy it to the new one, and kaboom. I think there's a broader refcounting problem with LARP mode -- the setxattr code can return to userspace before the CIL actually formats and commits the log item, which results in a UAF bug. Therefore, the xattr log item needs to be able to retain a reference to the name and value buffers until the log items have completely cleared the log. Furthermore, each time we create an intent log item, we allocate new memory and (re)copy the contents; sharing here would be very useful. Solve the UAF and the unnecessary memory allocations by having the log code create a single refcounted buffer to contain the name and value contents. This buffer can be passed from old to new during a relog operation, and the logging code can (optionally) attach it to the xfs_attr_item for reuse when LARP mode is enabled. This also fixes a problem where the xfs_attri_log_item objects weren't being freed back to the same cache where they came from. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-23xfs: do not use logged xattr updates on V4 filesystemsDarrick J. Wong2-4/+5
V4 superblocks do not contain the log_incompat feature bit, which means that we cannot protect xattr log items against kernels that are too old to know how to recover them. Turn off the log items for such filesystems and adjust the "delayed" name to reflect what it's really controlling. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: fix typo in commentJulia Lawall1-1/+1
Spelling mistake (triple letters) in comment. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: rename struct xfs_attr_item to xfs_attr_intentDarrick J. Wong4-36/+36
Everywhere else in XFS, structures that capture the state of an ongoing deferred work item all have names that end with "_intent". The new extended attribute deferred work items are not named as such, so fix it to follow the naming convention used elsewhere. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: clean up state variable usage in xfs_attr_node_remove_attrDarrick J. Wong1-5/+2
The state variable is now a local variable pointing to a heap allocation, so we don't need to zero-initialize it, nor do we need the conditional to decide if we should free it. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: put attr[id] log item cache init with the othersDarrick J. Wong3-52/+0
Initialize and destroy the xattr log item caches in the same places that we do all the other log item caches. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: remove struct xfs_attr_item.xattri_flagsDarrick J. Wong1-19/+13
Nobody uses this field, so get rid of it and the unused flag definition. Rearrange the structure layout to reduce its size from 104 to 96 bytes. This gets us from 39 to 42 objects per page. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: use a separate slab cache for deferred xattr work stateDarrick J. Wong3-1/+27
Create a separate slab cache for struct xfs_attr_item objects, since we can pack the (104-byte) intent items more tightly than we can with the general slab cache objects. On x86, this means 39 intents per memory page instead of 32. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: put the xattr intent item op flags in their own namespaceDarrick J. Wong3-8/+8
The flags that are stored in the extended attr intent log item really should have a separate namespace from the rest of the XFS_ATTR_* flags. Give them one to make it a little more obvious that they're intent item flags. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-22xfs: clean up xfs_attr_node_hasnameDarrick J. Wong3-31/+44
The calling conventions of this function are a mess -- callers /can/ provide a pointer to a pointer to a state structure, but it's not required, and as evidenced by the last two patches, the callers that do weren't be careful enough about how to deal with an existing da state. Push the allocation and freeing responsibilty to the callers, which means that callers from the xattr node state machine steps now have the visibility to allocate or free the da state structure as they please. As a bonus, the node remove/add paths for larp-mode replaces can reset the da state structure instead of freeing and immediately reallocating it. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-20xfs: reject unknown xattri log item filter flags during recoveryDarrick J. Wong1-1/+9
Make sure we screen the "attr flags" field of recovered xattr intent log items to reject flag bits that we don't know about. This is really the attr *filter* field from xfs_da_args, so rename the field and create a mask to make checking for invalid bits easier. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-20xfs: don't leak the retained da state when doing a leaf to node conversionDarrick J. Wong1-2/+8
If a setxattr operation finds an xattr structure in leaf format, adding the attr can fail due to lack of space and hence requires an upgrade to node format. After this happens, we'll roll the transaction and re-enter the state machine, at which time we need to perform a second lookup of the attribute name to find its new location. This lookup attaches a new da state structure to the xfs_attr_item but doesn't free the old one (from the leaf lookup) and leaks it. Fix that. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-20xfs: don't leak da state when freeing the attr intent itemDarrick J. Wong1-8/+14
kmemleak reported that we lost an xfs_da_state while removing xattrs in generic/020: unreferenced object 0xffff88801c0e4b40 (size 480): comm "attr", pid 30515, jiffies 4294931061 (age 5.960s) hex dump (first 32 bytes): 78 bc 65 07 00 c9 ff ff 00 30 60 1c 80 88 ff ff x.e......0`..... 02 00 00 00 00 00 00 00 80 18 83 4e 80 88 ff ff ...........N.... backtrace: [<ffffffffa023ef4a>] xfs_da_state_alloc+0x1a/0x30 [xfs] [<ffffffffa021b6f3>] xfs_attr_node_hasname+0x23/0x90 [xfs] [<ffffffffa021c6f1>] xfs_attr_set_iter+0x441/0xa30 [xfs] [<ffffffffa02b5104>] xfs_xattri_finish_update+0x44/0x80 [xfs] [<ffffffffa02b515e>] xfs_attr_finish_item+0x1e/0x40 [xfs] [<ffffffffa0244744>] xfs_defer_finish_noroll+0x184/0x740 [xfs] [<ffffffffa02a6473>] __xfs_trans_commit+0x153/0x3e0 [xfs] [<ffffffffa021d149>] xfs_attr_set+0x469/0x7e0 [xfs] [<ffffffffa02a78d9>] xfs_xattr_set+0x89/0xd0 [xfs] [<ffffffff812e6512>] __vfs_removexattr+0x52/0x70 [<ffffffff812e6a08>] __vfs_removexattr_locked+0xb8/0x150 [<ffffffff812e6af6>] vfs_removexattr+0x56/0x100 [<ffffffff812e6bf8>] removexattr+0x58/0x90 [<ffffffff812e6cce>] path_removexattr+0x9e/0xc0 [<ffffffff812e6d44>] __x64_sys_lremovexattr+0x14/0x20 [<ffffffff81786b35>] do_syscall_64+0x35/0x80 I think this is a consequence of xfs_attr_node_removename_setup attaching a new da(btree) state to xfs_attr_item and never freeing it. I /think/ it's the case that the remove paths could detach the da state earlier in the remove state machine since nothing else accesses the state. However, let's future-proof the new xattr code by adding a catch-all when we free the xfs_attr_item to make sure we never leak the da state. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12Merge branch 'xfs-5.19-quota-warn-remove' into xfs-5.19-for-nextDave Chinner1-1/+0
2022-05-12xfs: detect empty attr leaf blocks in xfs_attr3_leaf_verifyDave Chinner1-0/+9
xfs_repair flags these as a corruption error, so the verifier should catch software bugs that result in empty leaf blocks being written to disk, too. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: ATTR_REPLACE algorithm with LARP enabled needs reworkDave Chinner4-66/+128
We can't use the same algorithm for replacing an existing attribute when logging attributes. The existing algorithm is essentially: 1. create new attr w/ INCOMPLETE 2. atomically flip INCOMPLETE flags between old + new attribute 3. remove old attr which is marked w/ INCOMPLETE This algorithm guarantees that we see either the old or new attribute, and if we fail after the atomic flag flip, we don't have to recover the removal of the old attr because we never see INCOMPLETE attributes in lookups. For logged attributes, however, this does not work. The logged attribute intents do not track the work that has been done as the transaction rolls, and hence the only recovery mechanism we have is "run the replace operation from scratch". This is further exacerbated by the attempt to avoid needing the INCOMPLETE flag to create an atomic swap. This means we can create a second active attribute of the same name before we remove the original. If we fail at any point after the create but before the removal has completed, we end up with duplicate attributes in the attr btree and recovery only tries to replace one of them. There are several other failure modes where we can leave partially allocated remote attributes that expose stale data, partially free remote attributes that enable UAF based stale data exposure, etc. TO fix this, we need a different algorithm for replace operations when LARP is enabled. Luckily, it's not that complex if we take the right first step. That is, the first thing we log is the attri intent with the new name/value pair and mark the old attr as INCOMPLETE in the same transaction. From there, we then remove the old attr and keep relogging the new name/value in the intent, such that we always know that we have to create the new attr in recovery. Once the old attr is removed, we then run a normal ATTR_CREATE operation relogging the intent as we go. If the new attr is local, then it gets created in a single atomic transaction that also logs the final intent done. If the new attr is remote, the we set INCOMPLETE on the new attr while we allocate and set the remote value, and then we clear the INCOMPLETE flag at in the last transaction taht logs the final intent done. If we fail at any point in this algorithm, log recovery will always see the same state on disk: the new name/value in the intent, and either an INCOMPLETE attr or no attr in the attr btree. If we find an INCOMPLETE attr, we run the full replace starting with removing the INCOMPLETE attr. If we don't find it, then we simply create the new attr. Notably, recovery of a failed create that has an INCOMPLETE flag set is now the same - we start with the lookup of the INCOMPLETE attr, and if that exists then we do the full replace recovery process, otherwise we just create the new attr. Hence changing the way we do the replace operation when LARP is enabled allows us to use the same log recovery algorithm for both the ATTR_CREATE and ATTR_REPLACE operations. This is also the same algorithm we use for runtime ATTR_REPLACE operations (except for the step setting up the initial conditions). The result is that: - ATTR_CREATE uses the same algorithm regardless of whether LARP is enabled or not - ATTR_REPLACE with larp=0 is identical to the old algorithm - ATTR_REPLACE with larp=1 runs an unmodified attr removal algorithm from the larp=0 code and then runs the unmodified ATTR_CREATE code. - log recovery when larp=1 runs the same ATTR_REPLACE algorithm as it uses at runtime. Because the state machine is now quite clean, changing the algorithm is really just a case of changing the initial state and how the states link together for the ATTR_REPLACE case. Hence it's not a huge amount of code for what is a fairly substantial rework of the attr logging and recovery algorithm.... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: use XFS_DA_OP flags in deferred attr opsDave Chinner4-67/+84
We currently store the high level attr operation in args->attr_flags. This field contains what the VFS is telling us to do, but don't necessarily match what we are doing in the low level modification state machine. e.g. XATTR_REPLACE implies both XFS_DA_OP_ADDNAME and XFS_DA_OP_RENAME because it is doing both a remove and adding a new attr. However, deep in the individual state machine operations, we check errors against this high level VFS op flags, not the low level XFS_DA_OP flags. Indeed, we don't even have a low level flag for a REMOVE operation, so the only way we know we are doing a remove is the complete absence of XATTR_REPLACE, XATTR_CREATE, XFS_DA_OP_ADDNAME and XFS_DA_OP_RENAME. And because there are other flags in these fields, this is a pain to check if we need to. As the XFS_DA_OP flags are only needed once the deferred operations are set up, set these flags appropriately when we set the initial operation state. We also introduce a XFS_DA_OP_REMOVE flag to make it easy to know that we are doing a remove operation. With these, we can remove the use of XATTR_REPLACE and XATTR_CREATE in low level lookup operations, and manipulate the low level flags according to the low level context that is operating. e.g. log recovery does not have a VFS xattr operation state to copy into args->attr_flags, and the low level state machine ops we do for recovery do not match the high level VFS operations that were in progress when the system failed... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: remove xfs_attri_remove_iterDave Chinner1-279/+139
xfs_attri_remove_iter is not used anymore, so remove it and all the infrastructure it uses and is needed to drive it. THe xfs_attr_refillstate() function now throws an unused warning, so isolate the xfs_attr_fillstate()/xfs_attr_refillstate() code pair with an #if 0 and a comment explaining why we want to keep this code and restore the optimisation it provides in the near future. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: switch attr remove to xfs_attri_set_iterDave Chinner2-12/+19
Now that xfs_attri_set_iter() has initial states for removing attributes, switch the pure attribute removal code over to using it. This requires attrs being removed to always be marked as INCOMPLETE before we start the removal due to the fact we look up the attr to remove again in xfs_attr_node_remove_attr(). Note: this drops the fillstate/refillstate optimisations from the remove path that avoid having to look up the path again after setting the incomplete flag and removing remote attrs. Restoring that optimisation to this path is future Dave's problem. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: introduce attr remove initial states into xfs_attr_set_iterDave Chinner2-62/+81
We need to merge the add and remove code paths to enable safe recovery of replace operations. Hoist the initial remove states from xfs_attr_remove_iter into xfs_attr_set_iter. We will make use of them in the next patches. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: xfs_attr_set_iter() does not need to return EAGAINDave Chinner1-53/+37
Now that the full xfs_attr_set_iter() state machine always terminates with either the state being XFS_DAS_DONE on success or an error on failure, we can get rid of the need for it to return -EAGAIN whenever it needs to roll the transaction before running the next state. That is, we don't need to spray -EAGAIN return states everywhere, the caller just check the state machine state for completion to determine what action should be taken next. This greatly simplifies the code within the state machine implementation as it now only has to handle 0 for success or -errno for error and it doesn't need to tell the caller to retry. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: clean up final attr removal in xfs_attr_set_iterDave Chinner2-70/+91
Clean up the final leaf/node states in xfs_attr_set_iter() to further simplify the high level state machine and to set the completion state correctly. As we are adding a separate state for node format removal, we need to ensure that node formats are collapsed back to shortform or empty correctly. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: remote xattr removal in xfs_attr_set_iter() is conditionalDave Chinner2-33/+34
We may not have a remote value for the old xattr we have to remove, so skip over the remote value removal states and go straight to the xattr name removal in the leaf/node block. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: XFS_DAS_LEAF_REPLACE state only needed if !LARPDave Chinner2-52/+73
We can skip the REPLACE state when LARP is enabled, but that means the XFS_DAS_FLIP_LFLAG state is now poorly named - it indicates something that has been done rather than what the state is going to do. Rename it to "REMOVE_OLD" to indicate that we are now going to perform removal of the old attr. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: split remote attr setting out from replace pathDave Chinner2-56/+71
When we set a new xattr, we have three exit paths: 1. nothing else to do 2. allocate and set the remote xattr value 3. perform the rest of a replace operation Currently we push both 2 and 3 into the same state, regardless of whether we just set a remote attribute or not. Once we've set the remote xattr, we have two exit states: 1. nothing else to do 2. perform the rest of a replace operation Hence we can split the remote xattr allocation and setting into their own states and factor it out of xfs_attr_set_iter() to further clean up the state machine and the implementation of the state machine. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: consolidate leaf/node states in xfs_attr_set_iterDave Chinner2-109/+27
The operations performed from XFS_DAS_FOUND_LBLK through to XFS_DAS_RM_LBLK are now identical to XFS_DAS_FOUND_NBLK through to XFS_DAS_RM_NBLK. We can collapse these down into a single set of code. To do this, define the states that leaf and node run through as separate sets of sequential states. Then as we move to the next state, we can use increments rather than specific state assignments to move through the states. This means the state progression is set by the initial state that enters the series and we don't need to duplicate the code anymore. At the exit point of the series we need to select the correct leaf or node state, but that can also be done by state increment rather than assignment. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: kill XFS_DAC_LEAF_ADDNAME_INITDave Chinner2-24/+27
We re-enter the XFS_DAS_FOUND_LBLK state when we have to allocate multiple extents for a remote xattr. We currently have a flag called XFS_DAC_LEAF_ADDNAME_INIT to avoid running the remote attr hole finding code more than once. However, for the node format tree, we have a separate state for this so we never reenter the state machine at XFS_DAS_FOUND_NBLK and so it does not need a special flag to skip over the remote attr hold finding code. Convert the leaf block code to use the same state machine as the node blocks and kill the XFS_DAC_LEAF_ADDNAME_INIT flag. This further points out that this "ALLOC" state is only traversed if we have remote xattrs or we are doing a rename operation. Rename both the leaf and node alloc states to _ALLOC_RMT to indicate they are iterating to do allocation of remote xattr blocks. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-12xfs: separate out initial attr_set statesDave Chinner3-95/+157
We current use XFS_DAS_UNINIT for several steps in the attr_set state machine. We use it for setting shortform xattrs, converting from shortform to leaf, leaf add, leaf-to-node and leaf add. All of these things are essentially known before we start the state machine iterating, so we really should separate them out: XFS_DAS_SF_ADD: - tries to do a shortform add - on success -> done - on ENOSPC converts to leaf, -> XFS_DAS_LEAF_ADD - on error, dies. XFS_DAS_LEAF_ADD: - tries to do leaf add - on success: - inline attr -> done - remote xattr || REPLACE -> XFS_DAS_FOUND_LBLK - on ENOSPC converts to node, -> XFS_DAS_NODE_ADD - on error, dies XFS_DAS_NODE_ADD: - tries to do node add - on success: - inline attr -> done - remote xattr || REPLACE -> XFS_DAS_FOUND_NBLK - on error, dies This makes it easier to understand how the state machine starts up and sets us up on the path to further state machine simplifications. This also converts the DAS state tracepoints to use strings rather than numbers, as converting between enums and numbers requires manual counting rather than just reading the name. This also introduces a XFS_DAS_DONE state so that we can trace successful operation completions easily. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: remove warning counters from struct xfs_dquot_resCatherine Hoang1-1/+0
Warning counts are not used anywhere in the kernel. In addition, there are no use cases, test coverage, or documentation for this functionality. Remove the 'warnings' field from struct xfs_dquot_res and any other related code. Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: rework deferred attribute operation setupDave Chinner3-70/+98
Logged attribute intents only have set and remove types - there is no separate intent type for a replace operation. We should have a separate type for a replace operation, as it needs to perform operations that neither SET or REMOVE can perform. Add this type to the intent items and rearrange the deferred operation setup to reflect the different operations we are performing. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: make xattri_leaf_bp more usefulDave Chinner1-18/+32
We currently set it and hold it when converting from short to leaf form, then release it only to immediately look it back up again to do the leaf insert. Do a bit of refactoring to xfs_attr_leaf_try_add() to avoid this messy handling of the newly allocated leaf buffer. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: avoid empty xattr transaction when attrs are inlineDave Chinner1-20/+19
generic/642 triggered a reproducable assert failure in xlog_cil_commit() that resulted from a xfs_attr_set() committing an empty but dirty transaction. When the CIL is empty and this occurs, xlog_cil_commit() tries a background push and this triggers a "pushing an empty CIL" assert. XFS: Assertion failed: !list_empty(&cil->xc_cil), file: fs/xfs/xfs_log_cil.c, line: 1274 Call Trace: <TASK> xlog_cil_commit+0xa5a/0xad0 __xfs_trans_commit+0xb8/0x330 xfs_trans_commit+0x10/0x20 xfs_attr_set+0x3e2/0x4c0 xfs_xattr_set+0x8d/0xe0 __vfs_setxattr+0x6b/0x90 __vfs_setxattr_noperm+0x76/0x220 __vfs_setxattr_locked+0xdf/0x100 vfs_setxattr+0x94/0x170 setxattr+0x110/0x200 path_setxattr+0xbf/0xe0 __x64_sys_setxattr+0x2b/0x30 do_syscall_64+0x35/0x80 The problem is related to the breakdown of attribute addition in xfs_attr_set_iter() and how it is called from deferred operations. When we have a pure leaf xattr insert, we add the xattr to the leaf and set the next state to XFS_DAS_FOUND_LBLK and return -EAGAIN. This requeues the xattr defered work, rolls the transaction and runs xfs_attr_set_iter() again. This then checks the xattr for being remote (it's not) and whether a replace op is being done (this is a create op) and if neither are true it returns without having done anything. xfs_xattri_finish_update() then unconditionally sets the transaction dirty, and the deferops finishes and returns to __xfs_trans_commit() which sees the transaction dirty and tries to commit it by calling xlog_cil_commit(). The transaction is empty, and then the assert fires if this happens when the CIL is empty. This patch addresses the structure of xfs_attr_set_iter() that requires re-entry on leaf add even when nothing will be done. This gets rid of the trailing empty transaction and so doesn't trigger the XFS_TRANS_DIRTY assignment in xfs_xattri_finish_update() incorrectly. Addressing that is for a different patch. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Henderson<allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: add leaf to node error tagAllison Henderson2-1/+9
Add an error tag on xfs_attr3_leaf_to_node to test log attribute recovery and replay. Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: add leaf split error tagAllison Henderson2-1/+7
Add an error tag on xfs_da3_split to test log attribute recovery and replay. Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: Add helper function xfs_init_attr_transAllison Henderson2-10/+25
Quick helper function to collapse duplicate code to initialize transactions for attributes Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Suggested-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: Add helper function xfs_attr_leaf_addnameAllison Henderson1-50/+60
This patch adds a helper function xfs_attr_leaf_addname. While this does help to break down xfs_attr_set_iter, it does also hoist out some of the state management. This patch has been moved to the end of the clean up series for further discussion. Suggested-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-11xfs: Merge xfs_delattr_context into xfs_attr_itemAllison Henderson4-121/+123
This is a clean up patch that merges xfs_delattr_context into xfs_attr_item. Now that the refactoring is complete and the delayed operation infrastructure is in place, we can combine these to eliminate the extra struct Signed-off-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>